Governing fuel pump



May'zs, 1923.'

A. F. CHRISTMAS GOVERNING FUEL PUMP Filed sem. 15, 192.0

o 1 U W Y Q II o o 1f u@ @X175 INVENTOR a ATTo'R EY Patented May 29, 1923. i

UNITED STATES team PATENT ortica.

COMPANY, OF JERSEY CITY,

NEW JERSEY, A CORPORATION 0F NEW JERSEY.

GOVERNING FUEL PUMP.

Application led `Septen'iber 15,` 1920. Serial No. 410,461.

T 0 all whom t may concern.'

Be it kno-wn that. I, ADoLriI F. CHRisTMAs, a citizen of the United States, and a resident of Easton, county of Northampton, State of Pennsylvania, have invented certain new and useful Improvements in Governing Fuel Pumps, of which the following is a specification.

This invention relates to a fuel pump, but

more especially to a pump adapted to force l liquid fuel, suchv as fuel oil, fro-m a source of supply into the combustion chamber ofan internal combustion' engine. Suc-h a 'governing fuel pump'is provided with means for controlling or varying the amount of fuel 'pumped into the combustion chamber in order to maintain a substantially constant speed of the engine under varying conditions of load.

The primary objects of the present invention are to more accurately co-ntrol and varythe amount of fuel requiredsat each stroke, enable the pump to start pumping the fuel at a fixed point in the stroke of the engine, and continue the delivery until vthe required amount of fuel orl oil has been admitted to the combustionv chamber and then receive the remaining oil displaced by the pump plunger in a separate closed chamber.

Another object of the invention is to secure a fuel pump for internal combustion engines which will be exceedingly sensitive to variations in the position of the governor and yet will he simple, rugged and not easily put out of order.

To these ends the invention is shown in the accompanying drawings, in which- Figure l is a side elevation partly in vertical sectio-n of a governing fuel pump constructed in accordance with my invention and mounted on a combustion. engine, the frame of which is shown broken away,

Figure 2 is a longitudinal sectional elevation taken through the fuel pump, and

Figure 3 is a view similar to Figure 2 with the parts in a different position.

Referring to the dra-wings, A represents the base of a combustion engine having a portion of the cylinder indicated at B. The

fuel governing pump in this instance comprises a frame C adapted to be conveniently connected to the engine as by mea-ns of the bolts D and provided with the pump chamber E to which the inlet pipe F and the discharge pipe G are suitably connected and provided with the inlet valve H and the discharge valve J, in this instance shown in the form of ball valves, although it is to be understood that any desired form of valves may be used. The inlet pipe F may be connected to any suitable source of supply of liquid fuel, as for instance fuel oil, and the discharge pipe G is adapted to be connected to the comb-ustion head of the cylinder B as usual. v

A pump plunger J is adapted to reciprocate in the pump-chamber El and suitable means -are provided operatively connected to a rotating or reciprocating member of the engine for actuating the pump plunger in accordance with the stroke of the engine. In this instance a cam K is rigidly mounted on a rock shaft L provided with a crank arm O having a rod P pivotally attached thereto, which may for instance be connected to be operated from the fly wheel of the engine. As the rod P reciprocates, the cam K is rocked backward and forward for actuating lthe pump plunger J', and its operative parts.

As shown, the p'ump plunger J is hollow having a larger bore Q, anda smaller bore R communicating with a chamber S in the pump plunger head T. The pump plunger head T slides within the frame C and a supplementary piston head U operates within vthe closed chamber S and is provided with a V adapted to bear on the bearing por- W of the head T for pushing the head and plunger J inwardly and also to open and close the chamber S for the admission and discharge of oil. The stop V is provided with a reduc-ed shank V having a spring W( thereon for maintainingthe stop V against the bearing portion W of the head.

A stuffing gland X is preferably provided for the pump plunger and a compression spring Y is shown interposed between the plunger head T and the abutment formed by the stuiiiing gland X, for retracting the pump plunger as the cam U moves backwar l The operation of the pump plunger is controlled and regulated in accordance vwith the speed of the engine by means of a suitable centrifugal governor Z of any desired type, which may be mounted on the lframe C as shown and connected to actuatea-roller a (ii-other suitable regulated device adapted to be adjusted in position between the plunger head T and the toe b of the cam K as the governor rod c moves vertically in stop tion

accordance with the position of the governor balls d. As shown the governor rod c is pivoted at e to the lever arm f which carries the link g having the ro-ller a at its end.

In the operation of the device let it be assumed that the governor Z has raised the roller a to the position indicated in Figures l and 2, in which case the heel L of the cam K bears against the supplementary piston head U and through the agency of the stop V forces the plunger head T and pump plunger J inwardly on the discharge stroke with the stop V bearing against its bearing` lV and all the oil drawn into the hollow pump plunger on the suction stroke is forced through the discharge pipe G to the combustion head of the engine. If the speed of the machine increases due to decreased load or for any other reason, the governor. Z drops the roller L further down between the toe b of` the cam for instance as in Figure 3, so that the toe of the cam strikes against the roller o and forces the plunger head T and plunger J forwardly on the discharge stroke a given distance before the heel of the cam bears against the supplementary piston U, thus moving the head T away from the stop -V and permit--- ting the oil in the pump chamber to pass through the plunger into the chamber S where it is retained so that no oil is supplied to the combustion head of the engine for a given time and the speed is brought back to normal.

As lon as the stop V remains against the bearmg l the fuel pumped by the plunger J must pass into the discharge pipe G but with different positions of the roller a, different amounts of fuel will be supplied to the combustion chamber of the engine in accorda-nce with the speed and requirements of the engine. The oil received in the chamber S will be discharged therefrom or at least a portion of such oil will be discharged back into the pump chamber when the partsresume the operative relation indicated in Figure 2, in which the outer surface of the supplementary piston head U is substantlally Hush with the outer surface of the pump plunger head T. The pump plunger is furthermore so adjusted and connected with the operative parts of the engine, that the opening of the chamber S takes place at variable points toward the end of the stroke 0f the plunger J to vary the amount of'fuel admitted to the combustion chamber of the engme.

I claim:

l. In a fuel pump for internal combustion engines, a (plunger adapted to reciprocate Within a cylinder to force motive fluid from a source of supply into a combustion chamber, means for'actuating said plunger, a

to said plunger actuating means for vary-- ing the opening of said chamber to vary the length of time during which fuel is admitted to the combustion chamber Without by-passing fuel back to the supply pipe.

2. In a fuel pump for internal combustion engines, a plunger adapted to reciprocate within a cylinder to force motive fluid from a source of supply into a combustion chamber, means for actuating said plunger, a closedchamber within said plunger, a spring actuated stop controlling said chamber and means operatively connected to said plunger actuating .means and controlled by a governor to open said chamber for receiving and returning a portion of fuel from the plunger cylinder and vary the amount of fuel supplied to the combustion chamber without bypassing fuel back to the supply pipe.

3. In a fuel pump for internal combustion engines, a plunger operating within a cylinder to force fuel oil into an internal combustion engine, a closed chamber Within said plunger, a stop normally held against a bearing 011 the plunger and locating within said plunger for controlling said chamber, means for operating said plunger and means located in operative engaging relation to said plunger operating meansy and under the con trol of a governor to open said chamber for receiving and directlyreturning a portion of the fuel oil from the plunger cylinder for a predetermined time without stopping the engine without by-passing fuel back to the supply pipe.

4. In a fuel pump for internal combustion engines, a plunger operating within a cylinder to force fuel oil into said engine, a closed chamber Within the plunger, a stop control/ling said chamber and normally held against a bearing on the plunger, and means bearing directly against one end of said plunger under the control of a governor to open said chamber for receiving and retaining a portion of the fuel from the plunger cylinder for a given time Without stopping Vthe engine and without by-passing fuel back to the supply pipe.

In testimony whereof I have signed this specification.

DOLPH F. CHRISTMAS. 

